RE: Bug 6463: Attaching Policy to WS-Mex GetMetadata - Marked up proposal

Thanks Katy.

Here are some initial comments on the proposal.

>In Example 8-1, a [WS-Addressing] endpoint reference to a service endpoint contains the metadata to allow requesters to issue a GetMetadata request against it

We are afraid that the proposed Example 8-1 does not provide sufficient protocol binding information to allow requesters to issue a GetMetadata request against a service endpoint. For instance, how can a requester infer what is the version of SOAP? What is the underlying protocol transport?

We think that the WS-MetadataExchange specification should provide an example that provides sufficient binding information, including policies (to address issue 6463), to bootstrap.

>As an alternative to using MetadataLocation (lines 08-17), the WS-MetadataExchange WSDL containing the appropriately attached policy could have been embedded directly into the MetadataSection.  The embedded WSDL approach was used in example Example 7.1 to pass metadata in the EPR.

The description of the alternative sounds right. But, example 7.1 describes how to embed service metadata within an EPR. These are two different use cases. It might help to show case an example that illustrates how to embed a bootstrap binding in an EPR and how to attach a policy expression (to address issue 6463) to the bootstrap binding.

We will be more than happy to work with Katy to prepare a revised proposal.

Regards,

Asir S Vedamuthu
Microsoft Corporation

From: public-ws-resource-access-request@w3.org [mailto:public-ws-resource-access-request@w3.org] On Behalf Of Katy Warr
Sent: Monday, December 07, 2009 10:42 AM
To: public-ws-resource-access@w3.org; Asir Vedamuthu
Subject: Bug 6463: Attaching Policy to WS-Mex GetMetadata - Marked up proposal


Following my action to create a markup version of the proposal for bug http://www.w3.org/Bugs/Public/show_bug.cgi?id=6463, please find the marked up document attached.  The changes are all in Section 8 (and an example is moved from section 7).



Asir,

The difference between your example and my previous one is primarily that you have embedded the WSDL metadata within the EPR, rather than using Policy Attachments.

Whilst both approaches work, I believe that we should have a wider variation of examples within the specification in order to illustrate different features and usage scenarios. From my experience, a wide range of examples is of great benefit to developers.  Embedded WSDL is already illustrated in example 7-1.

In this particular example (8.1), policy attachments also work very well as it provides a mechanism to associate policy with a single operation without having the whole WSDL included within the EPR.

As a suggested compromise, I've included the policy attachments example (8-1) in the proposal attached to this mail, but added a detailed explanation below it in order to aid understanding.  I have also added some text to say that the WSDL could be embedded, as an alternative approach.

Regards
Katy


________________________________


Unless stated otherwise above:
IBM United Kingdom Limited - Registered in England and Wales with number 741598.
Registered office: PO Box 41, North Harbour, Portsmouth, Hampshire PO6 3AU